This is a classic teapot design from the town of Yixing in Zhejiang Province, China, where teapots have been made for over 3,000 years. Yixing teapots are prized among tea connoisseurs throughout China for both their craftsmanship and their use of "purple sand" in crafting the pot. Yixing teapots season as they are used, until eventually (according to legend) one doesn't need to add tea leaves at all!
This style is known as a "curved" Yixing teapot. There's hardly a straight line on it, and its graceful shape is meant to recall the shape of water pouring out of a fine teapot.